BIODIVERSITY THE VARIETY OF LIFE ON EARTH AND THE ESSENTIAL INTERDEPENDENCE OF ALL LIVING THINGS Learning Goals & Success Criteria Understand the variation of life on the planet Describe the interdependence of living organisms Describe the major threats to biodiversity Variation of Life on the Planet The HUGE variation of life on the planet Common Name: Brown Antechinus Size: 70-140mm (~28g) Conservation Status: Least Concern Distribution: Northern & Eastern Australia Habitat: Woodland and forest habitats Antechinus stuartii The HUGE variation of life on the planet Common Name: Red Kangaroo Size: Males up to 1.4m and 92kg Conservation Status: Least Concern Distribution: Semi-arid and Arid regions of Australia Habitat: Sparsely wooded or open plains; grassland, shrubland, desert, woodland and open forest, and are most common in open savanna woodland. Macropus rufus There is diversity in Aquatic Ecosystems There is diversity in Terrestrial Ecosystems Biodiversity Hotspot A biodiversity hotspot is a biogeographic region that is both a significant reservoir of biodiversity and is threatened with destruction. The term ”biodiversity hotspot” specifically refers to 25 biologically rich areas around the world that have lost at least 70 percent of their original habitat. Terrestrial biodiversity hotspots 3 Levels of Biodiversity Genetic Diversity Different genes and combinations of genes within populations Different genes and combinations of genes within populations Species Definition: Organisms that have the potential to interbreed in nature and produce viable fertile offspring Population Definition: A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring Species diversity A number of different species represented in a given community Ecosystem diversity The variation of the ecosystems found in a region Global Ecosystem Diversity How diverse is the ocean? The ocean is not just the coral reef… There is the open ocean; the Antarctic; deep ocean; equatorial ocean. Each of these different habitats provides different diversity of species Global Ecosystem Diversity How diverse are the deserts? The desert is not just sand… There are also ice deserts; stony deserts; hot and dry; arid; coastal deserts; cold deserts. All these different types of deserts support very different species Global Ecosystem Diversity How diverse are the ice caps? The organisms that inhabit the Antarctic are very different to those that live in the Arctic. It’s not just the ice – what about under the ice? Global Ecosystem Diversity How diverse are our forests? Forests are not just the rainforests… There are temperate forests; mangrove forests; eucalypt forests; melaleuca forests; heathland – and that’s just Australia. All these different types of forests support very different species Which is more diverse? Which is more diverse? Which is more diverse? Which has more biodiversity? Classification of organisms There is biodiversity across the classification system. Vertebrates have 5 classes: Mammals Amphibians Reptiles Birds Fishes How many species in each of these classes? BIODIVERSITY LOSS WHAT IS CAUSING THE LOSS OF BIODIVERSITY ON OUR PLANET? Biodiversity Loss The main cause of the loss of biodiversity can be attributed to anthropogenic influences (the influence of human beings) on the world’s ecosystems. Human beings have deeply altered the environment, and have modified the terrestrial and aquatic ecosystems in many ways. Threats to Biodiversity The HIPPO acronym is a good way to remember the five main threats to biodiversity Habitat Loss Invasive Species Pollution Population (overpopulation) Overfishing, overuse, overexploitation 1. Habitat Loss Habitat loss is the greatest reason for biodiversity loss Long term Habitat Loss in NZ 2. Invasive/Exotic Species Introduced usually by human activities They are generally thought to cause economic or environmental harm Are all invasive/introduced species harmful? Some introduced species are beneficial to society Introduced species provide food, shelter, medicine, and aesthetic pleasure Some organisms are introduced to control the populations of invasive species - biocontrol Cactoblastis cactorum: Cactus Moth Prickly Pear cactus introduced to Australia It very quickly took over – particularly in NSW Cactoblastis cactorum was then introduced to Australia to control the Prickly Pear. It has managed to kill off over 99% of prickly pear in NSW. • Mango • Beef • Bacon (what’s not to love about bacon…) • Avocado • All introduced to Australia and enjoyed on dinner plates around the country 3. Pollution Pollution: oil spills, human agricultural waste, fertilisers, pesticides, acid deposition, greenhouse gases, etc Caused by human activities Has a negative effect on biodiversity 4. Population (overpopulation) 3.7 billion and counting The expansion of human population and affluence, especially in the developing world harms natural ecosystems Compare to our Biodiversity Hotspots Can you see the problem? 5. Overharvesting, overuse, overexploitation Overhunting, overfishing, destructive harvesting practices (cyanide, dynamite), illegal trade, exotic pet industry Compare fish landings in tons from 1910 and the late 1960s/early 1970s. What do you think caused the significant drop in fish landings between 1965 and 1975? What do you think is the outcome for fish this century?